South African scientists have confirmed the existence of four new varieties of chameleons. These reptiles belong to the genus Nadzikambia and were found in mountainous forest regions, known as “sky islands”, located in Mozambique.
Such species are considered cryptic, which means that they do not present visible physical traits that distinguish them from the two other species of the genus Nadzikambia already recorded: Nadzikambia mjalensis, from Malawi, and N. baylissi, found in Mozambique.
The remote location and complicated access to these habitats were crucial factors in these animals remaining unidentified by researchers for a long period.
Each of the new species was discovered in a different mountain in Mozambican territory. The geographic isolation of these populations on so-called mountainous “islands”, an evolutionary process that began approximately 6 million years ago, resulted in the emergence of these four new varieties. These “sky islands” are unique ecosystems, functioning as biodiversity refuges where physical separation by warmer plains or valleys drives the evolution of endemic species, highlighting their crucial importance for wildlife maintenance and global evolutionary studies. Among the new species are: N. franklinae, named in tribute to the British chemist Rosalind Franklin (1920-1958), responsible for discovering the double helix structure of DNA; N. goodallae, which celebrates activist and primatologist Jane Goodall (1934-2025); N. evanescens, whose literal meaning is “disappearing”, an alert to the species’ threatened status; and N. nubila, derived from the Latin “cloud”, referring to the characteristics of mountains covered by mist, the habitat of this reptile.
The detailed description of the discovery was published in April this year, in the specialized journal Vertebrate Zoology. The study is authored by Krystal Tolley, professor of zoology at the University of Johannesburg, and Werner Conradie, curator of herpetology at the Port Elizabeth Museum (Humewood), as well as a researcher at Nelson Mandela University, in George (South Africa).
The genus Nadzikambia, commonly called wild chameleon, encompasses species that have a mostly arboreal behavior. These animals mainly inhabit the tree canopy, where they look for insects and other invertebrates to feed on.
As the research points out, the arboreal way of life and the visual similarity of these lizards with already known species contributed to them not being noticed for so long.
“People did not usually look up in search of these animals. The incredible camouflage ability of chameleons in their environment made them difficult to identify, even in lower trees. To locate them in these mountains, it took considerable effort”, explained the researcher involved in the study.
During the study, scientists examined a total of 46 specimens of the genus Nadzikambia. These specimens were stored at the Port Elizabeth Museum and the Natural History Museum in London, also including those collected by Tolley’s team in the mountainous forest areas of Mozambique.
The researchers employed a total evidence analysis, which combined morphological information, such as scale count and internal structure, with genetic data. This genetic data was extracted from three nuclear genes and one mitochondrial DNA gene, transmitted exclusively through the maternal lineage.
Externally, however, chameleons demonstrated minimal morphological variation, both in the number of scales and their pigmentation.
“At this point, DNA analysis tools become fundamental. Despite the external similarity, each species has exclusive genetic signatures. The magnitude of the differences found in the genes analyzed provides us with great confidence that they are truly distinct species”, highlighted the study.
“These tropical forests are completely separated by extensions of savannah with a drier climate”, explained the biologist. “This means that, for millions of years, there was no genetic exchange between the chameleon populations on each of these ‘islands’. The genetic diversity observed today between the species allows us to calculate that this isolation process began approximately 5 to 6 million years ago.”
The research also highlighted the importance of conserving these newly discovered species. Fast-paced deforestation in Mozambique poses a serious threat to the particular ecosystem where Nadzikambia chameleons inhabit. The authors therefore decided to incorporate the names of environmental activists in the epithets of some of the lizards, seeking to highlight the relevance of their actions.
“Regrettably, the women of science who inspired the names of the species of Monte Namuli [N. franklinae] and Monte Ribáuè [N. goodallae] are no longer alive on the date of publication of this work, but we feel honored to pay this tribute”, declared the study authors.
“Jane Goodall, although focused on chimpanzees [Pan troglodytes] rather than chameleons, has dedicated much of her life to research in forested environments. The degradation of forests and other habitats, both on Mount Ribáuè and in the regions of Central and West Africa where P. troglodytes is found, is pushing species that depend on these ecosystems to the brink of extinction,” the scientists concluded.
